058 | Olfactory signaling and social entrainment of circadian rhythms


Author: Chiara Costa | Email: chcostapetrillo@gmail.com

Chiara Costa 1°2°, Martina Radice 1°2°, Esteban Javier Beckwith 1°2°, Nicolás Pírez 1°2°

1° Instituto de Fisiología, Biología Molecular y Neurociencias; UBA-CONICET, Argentina
2° Departamento de Fisiología, Biología Molecular y Celular; Facultad de Ciencias Exactas y Naturales; Universidad de Buenos Aires, Argentina

The olfactory system plays a crucial role in the capacity of social cues to synchronize the circadian clock. The goal of this project is to dissect the mechanisms that underlie locomotor activity entrainment by social interactions employing Drosophila melanogaster. We performed experiments using two fly lines entrained at different light schedules: a white-eye mutant entrained to a light schedule that is advanced 6 hours relative to a wild type (WT) strain. After a week of social interactions in darkness between the two groups in a ratio 70:30, the activity of the flies was individually recorded for 4 days. We observed that the majoritarian population was able to entrain the minoritarian one, regardless the genotype of the group in greater proportion. To test if this entrainment was through olfactory cues, we used a cannula to connect the interacting populations, only allowing the passive passage of volatile molecules. We found that flies in the minoritarian group were entrained to the phase of the majoritarian group, in spite of which group (advanced or delayed) was the majority. We also performed social interactions between WT and an anosmic mutant population that do not resynchronize their phase.
Combining genetics and immunocitochemistry strategies, as well as available connectome datasets, we are investigating how the olfactory system output neurons connects to the circadian relevant circuits.